Saturday was always going to be the big day at Ultra this year -- less of the warm-up, not the sparse crowds that strangely afflicted notable sets on Friday, and none of the inevitable "final day of a festival, it's Monday tomorrow" anxieties that will be felt Sunday. It was also a beautiful sunny day in downtown Miami, and the programming offered a highly eclectic and musically expansive lineup that positively invited you to arrive early, grab a beer, and wander among the eight stages.

U.K. dubstep pioneers Skream and Benga were given a strangely early billing at UMF Brasil, the de facto dubstep/bass stage of the day. The south London duo were clearly wired to play Miami and, backed up by hypeman Sgt. Pokes, they threw down a big early set that got the whole tent dancing. Slices of garage, '90s house, and old-skool breaks were interspersed within the predominant bass drops; the duo distinguished themselves easily from the glut of other dubstep artists through an innate sense of character and natural willingness to progress the genre.

The Klipsch Amphitheatre had an impressive lineup throughout the late afternoon and evening and became somewhat of an escape for those wishing to remove themselves from the rafts of commercial house and trance that dominates the main stage. Little Dragon confronted a relatively meager crowd in the pure sweltering heat of the afternoon sun, yet the Swedish electro outfit's alluringly funky set gradually transformed the atmosphere. Singer Yukimi Nagano oozed sassy charismatic stage presence, and the nuanced synth-heavy vibe of the band sounded both highly modern and impeccably executed.

Metronomy has been bubbling away within the U.K. hipster scene for the past five years and finally gained international acclaim with the release of its third album, The English Riviera, last year. Today the U.K. four-piece were somewhat of a revelation; their jaunty and bombastic form of indie rock transferred well and gained an enthusiastic response. While previously essentially the solo project of frontman/songwriter Joe Mount, the new band format of Metronomy seemed to give them a dynamic and idiosyncratic edge. Penultimate track "The Look" sounded superb -- a subtly intricate and wistful pop-rock summer anthem, it sparked waves of dancing as smoke and fire flares were unexpectedly emitted from the stage. A band clearly with an intriguing future ahead.

As the night descended, the crowd swelled and the amphitheater was full as everyone awaited for indie-electro shoegaze heroes M83. The setting was immensely atmospheric, perfectly poised and... They don't appear. In the Ultra world, every set starts and ends as programmed, such is the size and efficiency of the event, and when it was 40 minutes past stage time and roadies were still sound-testing the drum kit, it was clear that something was amiss. DJ Miss Nine kept everything going with a strong set of electro-house, but there was clearly a problem.

Eventually they arrived 45 minutes late and immediately blasted out the unmistakable sharp synth blasts of "Midnight City." The track sounded so good -- epic, blissed-out, lost within waves of swirling electronics -- that it was almost worth the wait. But it was clear this was essentially a token appearance; frontman Anthony Gonzalez apologized for the technical problems; they played a jammed-out version of "Couleurs" and then left, having been onstage for less than 15 minutes.

It was a disappointing result to what was clearly an eagerly awaited set, and the huge crowd largely dispersed prior to DJ Shadow arriving to play Miami for the first time ever. He performed his set hidden from within a large three-dimensional spherical DJ pod that featured a mind-blowing display of visuals, graphics, and projections. He played a wide-ranging set of scratched hip-hop, primal breaks, and moments of electro and dubstep, featuring a selection of tracks from his seminal 1996 debut, Endtroducing... It all sounded immense -- the synergy of music and visuals perfectly coalesced and created an overall sense of free-form creativity and experimentalism.

As the day drew to a close, rumors floated around the festival of Madonna's appearance with Amicii on the main stage. This news seemed unimportant while watching Shadow soundtrack surreal and hypnotic images of kaleidoscope chain saws, interspersed within fractured glitches, Godzilla pastiches, and pixilated robots. Playing within the spherical orb -- called his "Shadowsphere" -- was clearly not just a way for Shadow to become more visually exciting; it seemed to inspire and offer new avenues of artistic freedom. A fine way to conclude a musically rich day.

Critic's Notebook

Overheard in the crowd, number one: "I'd waited 15 years for it and then it was just...?" [sigh] - some guy still coming to terms with New Order's slightly underwhelming set on Friday.

Overheard in the crowd, number two: "Fuck these guys, who gives a fuck -- they've only got one good song anyway and it's not even that fucking good..." -- a foul-mouthed "Midnight City" M83 fan annoyed at the technical problems that heavily delayed and shortened their set. They came onstage about 15 seconds later.